55 / 2021-05-31 13:23:48

Electrospun Nanofibers for Hydrophobic PVA Air Filter Paper with High Filtration Efficiency

Electrospinning technology; Hydrophobic polyvinyl alcohol (PVA-B); Hydrophilic polyvinyl alcohol (PVA-L); Filtration efficiency

Increased industrial pollution has led to a decline in environmental quality. The fine particulate matter in the air causes serious harm to the human body. As a filter medium, air filter paper has been widely used in various fields. The nanofibers prepared by electrospinning technology have the advantages of smaller specific surface area, simple operation and better fiber continuity. In this paper, the nanofibers deposited on the surface of cured air filter paper via electrospinning technology, a new type of electrospun nano-composite air filter paper with high filtration efficiency was formed. To enhance the durability of air filter paper, hydrophobic polyvinyl alcohol (PVA-B) with stearoyl chloride modified hydrophilic polyvinyl alcohol (PVA-L), was used for spinning to prepare hydrophobic polyvinyl alcohol air filter paper, simultaneously the hydrophilic polyvinyl alcohol air filter paper was prepared for contrast. The nanofibers prepared by electrospinning were evenly distributed on the surface, and the fiber structure inside the air filter paper has not changed. Fourier transform infrared analysis and contact angle analysis showed: the hydroxyl groups on the long chain of hydrophilic polyvinyl alcohol were replaced by ester groups, making the contact angle of hydrophobic polyvinyl alcohol air filter paper decreased from 123.5º to 118.4º in 1 h. The evenly distribution of nanofibers was observed by SEM. The pore size of hydrophobic polyvinyl alcohol air filter paper was reduced to 33% of the air filter paper. The filtration efficiency of hydrophobic polyvinyl alcohol air filter paper was 99.9955%, and the filtration accuracy of particles with different particle sizes in the range of 0.2-0.3 μm was higher than 95%, even though the initial resistance increased 23 Pa. This new type of composite air filter paper has improved filtration efficiency and filtration accuracy, and its application in high humidity environments, so that it has a higher development prospect in the future.